The present disclosure generally relates to container covers. More particularly, the present disclosure relates to disposable container covers, and automated methods for manufacturing container covers.
Disposable container covers capable of covering containers of various sizes and shapes have been in use for many years. Such covers typically include a plastic film, such as polyethylene, provided in sufficient dimension to overly the container opening. The film then employs surface tension or elastic bands to secure the film to the container, such as with Saran(copyright) wrap or Quick Covers(copyright), respectively, both being products of the present assignee, with the latter having an elastic band sewn directly to the film around its perimeter. The elastic band bordering the film is attached in such a manner that tension is created on the film, thereby creating a hollow enclosure with an expandable opening for placing atop and around containers of various sizes and shapes.
Use of these container covers is common for both perishable and nonperishable items. While these covers are beneficial in many respects, they are not without room for improvement. A common problem with existing container covers is their shape and the excessive amount of material used in constructing the covers. Specifically, much of the film utilized in the construction of conventional container covers is excessive with regard to the actual surface area needed to cover containers. For instance, typical container covers are constructed using a round piece of film and elastic for attachment at the border of the film. The tension created on the film by the elastic results in numerous pleats at the border of the film, therefore, when the cover is not fully expanded, much of the surface area of the cover is not utilized. This is especially true where the container being covered is much smaller than that for which the cover is, in its fully expanded state, capable of covering. While this manner of construction results in a functional container cover, much of the surface area of the film is not actually in use and is there only by default, as necessitated by the design of the cover. Also problematic of this design is the shapeless, relatively loose-fitting manner of coverage, which conventional covers typically provide. Among other things, this characteristic is directly related to the excessive material used in the construction of conventional container covers.
An additional problem with conventional container covers relates to manufacturing. Specifically, conventional container covers, as described above, require the slow, labor intensive manufacturing step of manually sewing an elastic band to the periphery of the film. These covers do not readily lend themselves to high-speed automated manufacturing, in turn, driving up the cost and time of manufacturing conventional container covers.
In accordance with one aspect of the disclosure, a container cover is provided which comprises two layers of ovate-shaped film situated planar to one another and heat sealed along their corresponding perimeters. Disposed in the second layer of film is a score line running between first and second points on the perimeter. A scored elastic strip is also attached to the second layer of film, wherein the score line of the elastic strip is aligned with the score line on the second layer of film. This manner of construction requires the user to create the container cover opening by pulling apart the scored layer of film, thereby creating an opening for placing atop a container. In accordance with another aspect of the disclosure, a container cover is provided wherein the first layer of film is perforated, thereby allowing for air and moisture ventilation through the container cover. Also embodied by the present disclosure is a container cover, wherein the first layer of film is rigid in comparison to the second layer. In accordance with yet additional aspects of the disclosure, container covers are provided wherein the elastic strip attached on the second layer of film is sewn directly to the film, heat sealed to the film, glued to the film, or otherwise attached to the film.
In accordance with another aspect of the disclosure, a method is provided for covering a container which comprises the steps of: (1) providing a container cover as described above having two layers of film cut in an ovate shape and attached at their perimeters, wherein one layer has a scored elastic strip aligned with a score line disposed in the film; (2) separating, by pulling apart, the scored layer of film at the score line of the film and the elastic strip, thereby creating an opening in the container cover; and (3) expanding the cover""s opening and placing the cover over a container with the separated layer of film adjacent to the walls of the container and the elastic strips gripping the container. Further provided by the disclosure is an additional step of situating the container cover over the container such that the film forms a dome over the container. Alternatively, the container cover of the present disclosure can be situated to fit closely atop a container.
In accordance with yet another aspect of the disclosure, a method of manufacturing a container cover is disclosed which comprises the steps of providing a first web of film; providing a second web of film having a elastic strip secured thereto; perforating both the elastic strip and the second web of film; cutting a shape through the web, second web, and elastic strip; and sealing the first web to the second web around their corresponding perimeters. Further provided by the present disclosure is the method of manufacturing the container cover above, wherein a heated knife is use to cut the first web, second web, and the elastic strip in an ovate shape. Also in accordance with the present disclosure are methods of manufacturing, wherein the elastic strip is provided in a pre-perforated form. Alternatively, in accordance with the present teachings is a method wherein both the elastic strip and the second of film are perforated using a rotating, toothed wheel.
These and other aspects and features of the disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.